British Journal of Medicine & Medical Research 6(1): 48-55, 2015, Article no.BJMMR.2015.183 ISSN: 2231-0614

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A Brief Overview of Oral Potentially Malignant Disorder

Y. Saleh Nasser Azzeghaib1*

1Department of Oral Maxillofacial Sciences, Alfarabi College of Dentistry and Nursing, Saudi Arabia.

Author’s contribution

The sole author designed, analyzed and interpreted and prepared the manuscript.

Article Information

DOI: 10.9734/BJMMR/2015/11491 Editor(s): (1) Li (Peter) Mei, Faculty of Dentistry, Discipline of Orthodontics, University of Otago, New Zealand. (2) Philippe E. Spiess, Department of Genitourinary Oncology, Moffitt Cancer Center, USA and Department of Urology and Department of Oncologic Sciences (Joint Appointment), College of Medicine, University of South Florida, Tampa, FL, USA. Reviewers: (1) Anonymous, Department of Oral Pathology, SMBT dental college & Hospital, Sangamner, Maharashtra, India. (2) Micha Cyrus, Department of Oral & Maxillofacial Surgery and , Oral Pathology School of Dental Sciences, University of Nairobi, Kenya. (3) Anonymous, University of Malaya, Malaysia. (4) Anonymous, JSS Dental College and Hospital, JSS University, Mysore, Karnataka, India. (5) Anonymous, Rajasthan Dental College and Hospital, Jaipur, India. Complete Peer review History: http://www.sciencedomain.org/review-history.php?iid=720&id=12&aid=7230

Received 18th May 2014 st Review Article Accepted 31 October 2014 Published 15th December 2014

ABSTRACT

Cancer of the oral cavity is one of the most common cancers. is still only detectable at a late stage, and the survival rate for an oral cancer patient has essentially remained unchanged over the past three decades. This study is concentrated on the oral precancerous lesions which are commonly seen in dental clinics and to give the general practitioners Knowledge for early detection of these lesions. A literature search was conducted using Medline, accessed via the National Library of Medicine PubMed interface, searching for articles relating to the precancerous oral lesions written in English.

Keywords: Precancerous lesion (potentially malignant disorder); oral lesion; malignant transformation.

1. INTRODUCTION part of the throat). Symptoms may include red, white and/or speckled spots and patches in the Oral cancer may develop in any part of the mouth, swellings, lumps and rough crusts areas mouth, tongue, and the oropharynx (middle anywhere inside the mouth, unexplained ______

*Corresponding author: Email: [email protected];

Azzeghaibi; BJMMR, 6(1): 48-55, 2015; Article no.BJMMR.2015.183

bleeding, pain, tenderness or numbness in the quid chewing commonly leads to precancerous mouth, difficulty in swallowing, speaking or condition known as chewing, hoarseness of voice, ear pain and which has a malignant transformation rate of dramatic loss in weight [1,2]. 7.6% 12). Prabhu and Wilson stated that Human papilloma virus (HPV) may also be associated The term Potentially Malignant Disorder has with some oral and oropharyngeal cancers [13]. been introduced in 2005 after the WHO meeting HPV-18 has been found in up to 14 percent of to be used instead of pre-malignant lesions and cases and HPV-16 has been detected in up to 22 conditions, they also suggested that percent of oral cancers [14-15]. The low intake of and have the highest malignant fruits and vegetables in the diet may also transformation behaviour and attention must be eventually attribute to an increased risk for given to them more than the other lesions. cancer [16] Radoï et al. [17] reported that hot Precancerous lesions and early oral cancers are beverages tea and coffeein particular drinking often subtle and asymptomatic. Therefore, it is may decrease the risk of oral cancer through important for the clinician to have suspicion, antioxidant components which play a role in the especially if risk factors such as tobacco use or reparations of cellular damages. Jaleel et al. [18] alcohol abuse is present [23]. Early detection and reported that people with the blood group A had diagnosis is very important issue and have direct a 10.46% likelihood to develop oral cancer relation in the treatment and prognosis of the oral compared to people of other blood groups. cancer. Plummer-Vinson or Paterson-Kelly syndrome which is an iron deficiency anemia in 2. RISK FACTORS combination with dysphagia and esophageal web is associated with an increased risk for Smokers are 5 to 9 times more likely to develop development of carcinoma of the oral cavity, oral cancer in comparison to nonsmokers, and particularly oropharynx and oesophagus [19]. for heavy smokers who smoke 80 or more cigarettes daily, the risk is 17 times greater [3-4]. 3. DIAGNOSIS OF PRE MALIGNANT Souto et al. [5] reported that the mean LESION (POTENTIALLY MALIGNANT percentage of aneuploid nuclei was statistically DISORDER) higher in the smokers with oral squamous cell carcinoma (93.65%), as compared to non- Pre-malignant lesion often presents itself as smokers (39.3%) (P<0.05). Souto et al. [5] either white or red patches in known concluded in his study that tobacco use is as leukoplakia or erythroplakia [20-23]. The responsible for an increased number of patient may initially notice the presence of a non- aneuploid nuclei in the oral epithelium. Bouquot healing ulcer when the cancer develops. Later- and Meckstroth [6] reported that West Virginia is stage symptoms may include loosening of teeth, the state with the highest per capita consumption bleeding, dysphagia, difficulty in wearing of smokeless tobacco, yet it has less , and development of a neck mass. For oral/pharyngeal cancer than the US average visual examination and palpation, it is Madani et al. [7] indicated that gutkha, supari - recommended that a tongue blade or dental areca nut- chewing tobacco (tobacco flakes), bidi mirror and a gloved hand can be used to retract smoking and mishiri (tobacco powder, which the lips and extend the cheeks. To assist with applied as a tooth and gum cleaner) are retraction and examination of the lateral borders independent risk for oral cancer. The use of of the tongue gauze can be used for wrapping smokeless tobacco appears to be associated the tongue. Pre-malignant lesions are most with a much lower cancer risk than that commonly found in the lateral borders of the associated with smoked tobacco [8,9]. Andre et tongue, the floor of the mouth, the posterior al. [10] reported that the heavy drinkers are 30 aspect of the cheek, and the oropharynx. It is times more likely to develop oral and recommended by the American Cancer Society oropharyngeal cancer in comparison to non- that an annual check-up for all individuals aged drinkers [10]. A synergistic effect of alcohol and 40 and older, and every three years for those smoking was observed by some authors. Risk of between the ages of 20 and 39 [24-25] is done. developing malignancy in patients who are both heavy smokers and drinkers is over one hundred It is also recommended by the society to improve times [10-11]. Another habit which has been the oral cancer survival rate, by educating strongly associated with increased risk for oral individuals via oral sessions and new ways of cancer is the chronic use of betel quid [12]. Betel awareness (Word Choice: In most cases

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advertisement or advertising usually refers to a very thick and opaque), speckled Fig. 3 (less product or services) to encourage patients to common; non-homogenous / heterogenous reduce (Word Choice) the risk of contracting oral leukoplakias has a high risk of malignant cancer. transformation) and verrucous [29]. Proliferative verrucous leukoplakia (Fig. 4) begins with 4. LEUKOPLAKIA conventional flat white patches that, over time, they tend to become much thicker and papillary Oral leukoplakia (OL) is a white patch or plaque in nature and may progress to verrucous that cannot be rubbed off and cannot be carcinoma. The condition is often seen in characterized clinically or histologically as any patients without any risk factors, characterized by other condition [26]. Leukoplakia has no widespread, multifocal sites of involvement and histologic connotation and should never be used has a high recurrence rate [30]. A study of 3,300 as a microscopic diagnosis. biopsies of oral leukoplakia by waldron and shafer showed that 19.9% of all leukoplakia When evaluating a patient suspected to have a showed some degree of epithelial dysplasia [31]. leukoplakia, a rough clinical diagnosis must be Dysplasia is more commonly seen in thicker done to exclude leukoplakia, for example any leukoplakia; therefore, a verrucous leukoplakia is oral white patch can be diagnosed as a the most likely to show dysplastic changes leukoplakia until it is proved that it is other compared to other forms [32]. Speckled condition (, ).Oral white leukoplakia or erythroplakia (leukoplakias red patches can easily develop due to local irritation. component) is at greatest risk for showing For example ,the thickened hyperkeratotic areas dysplasia or carcinoma [32]. on the alveolar ridges of the edentulous patients, especially in patients who do not wear a dental prosthesis (Fig. 1). This hyperkeratotic area is due to the epithelium protecting the area which is preferably termed “frictional keratoses” [27]. Chronic cheek chewing (morsicatio buccarum) which leads to hyperkeratotic changes must not be termed as a leukoplakia; these lesions are not potentially malignant and can return back to normal structure if the irritant is removed. Nicotine and tobacco pouch , are not categorized as aleukoplakias.

2. Shows homogeneous leukoplakia

According to Hosni et al. [32] erythroplakia and speckled leukoplakia show histopathological alterations which vary from epithelial dysplasia to invasive carcinoma and these lesions have a high potential for malignant tranformation.

Recent studies have shown that these lesions 1. Shows hyperkeratotic on the edentulous have malignant transformation rates ranging from areas of the alveolar ridges 8.9 to 17.5 percent [33-43]. Because of the smoking habits, leukoplakia is more common in The most common sites of leukoplakia are the men than women [44], but studies have shown buccal mucosa, alveolar mucosa ,and the lower that women with leukoplakia have a higher risk of ; however, lesions in the floor of mouth, lateral developing oral carcinoma [34]. tongue, and lower lip are most likely to show dysplastic or malignant changes [28-29]. There All the published data regarding the malignant are three clinical varieties are recognized transformation of oral leukoplakia in different homogeneous Fig. 2 (common; faintly white – countries have been included in Table 1.

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cases of erythroplakia, it was reported that 51 percent of these were invasive squamous cell carcinoma, 40 percent were carcinoma in situ or severe epithelial dysplasia, and the remaining 9 percent demonstrated mild-to- moderate dysplasia. This points to the fact that true erythroplakia has more malignant potential than leukoplakia. Villa et al. [46] indicated that Oral erythroplakia is identified as the one with the highest malignant transformation rates compared to other premalignant lesions.

6. NICOTINE STOMATITIS

Nicotine stomatitis is most common in men over 40 years of age. Pipe and cigar developed nicotine stomatitis condition, but it also occurs in 3. Shows speckled leukoplakia cigarette smokers. Nicotine stomatitis is a lesion that develops on the of some smoker [47]. It appears white with raised red dots. The lesion is persistent, continuing as long as smoking persists. There are usually no symptoms associated with this lesion, even when it is long standing [48]. If the smoking is discontinued or lessened, the lesion may reverse completely. hyperkeratosis and the minor salivary gland involved shows inflammatory reaction. Nicotinic stomatitis is completely different from the palatal changes of reverse smoking clinically and histopathologically [49,50].

7. FRICTIONAL KERATOSIS

Frictional keratosis is a reactive lesion that shows white lesion in the oral mucosa commonly associated with sharp margins of a broken tooth or ill-fitting dentures, it can be diagnosed by good history taking and good examination sometimes a biopsy should be taken and it is treated by removing the cause [12].

8. PALATAL CHANGES ASSOCIATED 4. Shows Proliferative verrucous leukoplakia WITH REVERSE SMOKING

5. ERYTHROPLAKIA Reverse smoking is a condition when putting the cigarette in reverse direction inside the mouth Erythroplakia is a lesion that refers to a red patch leads to white keratotic patches, red patches and that cannot be categorized clinically or ulceration [7]. pathologically as any other condition [45]. Erythroplakia patches may be located near, or This white keratotic patches may be due excess associated with, oral leukoplakias. Bouquot and keratin production and small red dots may result Whitaker [31] suggested that erythroplakia may from an inflamed opening of a minor salivary occur with leukoplakia in the stage called gland in the palate, ulceration occurs due to the erythroleukoplakia. Erythroplakia has been heat which comes from the end of the cigarette considered the most severe form among all of which is placed inside the mouth [7]. the oral premalignant lesions because of its high malignant potential [32]. In a study done on 65

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Table 1. Shows the malignant transformation of oral leukoplakia in different countries

Authors Country Year Number of % of Patients with patients malignant transformation Einhorn and Wersäll Sweden 1967 782 4.0 2010 [44] Silverman 2013 [45] United States 1968 117 6.0 Pindborg et al. Denmark 1968 248 4.4 2011 [46] Kramer 2003 [47] England 1969 187 4.8 Roed-Petersen Denmark 1971 331 3.6 1971 [48] Bánóczy 1996 [49] Hungary 1977 670 6.0 Silverman et al. United States 1984 247 17.5 2001 [50] Lind 1987 [51] Norway 1987 157 8.9 Bouquot and United States 1986 463 10.3 Gorlin 1986 [52] Lan AX 2009 [53] China 2009 409 12.7 Amsterdam 2014 [54] Amsterdam 2014 144 2.6

9. ORAL SUB MUCOUS FIBROSIS at an early stage is believed to be the most effective means of reducing rates of death and Oral sub mucous fibrosis is a lesion commonly morbidity [22]. Early diagnosis depends upon found and prevalent in India, this lesion has a clinician or patient who may identify a suspicious high rate of malignant transformation to lesion or symptom while it is still at an early squamous cell carcinoma, the etiology of oral stage. sub mucous fibrosis is unknown but some of the risk factors involved are chewing of areca betel A white or red patch should be carefully nut and eating chili peppers, deficiency of iron inspected for a change insize, color, mobility, and B complex vitamins and folic acid and auto contour, texture, or function of intraoral, extra immune factor and genetic predisposition, oral or perioral tissue should arouse suspicion of symptoms of this lesion includes dryness of the the presence of malignant or premalignant mouth, dysphagia when the esophagus is lesions in these regions. All medical and dental involved and it can lead to hearing loss due to examination should include comprehensive head blockage in the Eustachian tubes, the affected and neck examinations with biopsy and further areas appears smooth, atrophic and almost white investigations when indicated. Any white lesion and looks pallor due to the fibrosis and ischemia must be considered a potentially malignant [12], mostly affect area are the buccal mucosa disorder until proven otherwise. General and the soft palate in the oral mucosa and these practitioners must spend more time examining areas lose their resilience and elasticity leading their patients thoroughly. to difficulty in mouth opening () and difficulty in eating, Oral sub mucous fibrosis can CONSENT easily spread from the oral cavity into the pharynx and the esophagus [7]. Not applicable.

10. CONCLUSION ETHICAL APPROVAL

Oral cavity and oro-pharnx region should be Not applicable. carefully inspected while examination especillay in heavy smokers and drinkers. Survival from COMPETING INTERESTS oral cancer has very poor rates, at approximately 50% overall [21], and have not improved in recent decades despite advances in therapeutic Author has declared that no competing interests interventions [51,52,53,45]. Detecting oral cancer exist.

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